ImpulseGundam

I recently acquired a 2000 Subaru Forester L, with 115k miles. We've only had it for 2 days, and we noticed something really weird. We were at a Subaru dealership for coolant, an oil filter, and some gear oil. However, because it was Labor Day, they were closed. As we were backing up to leave, it seemed to stutter a lot, and stuttered when we made some tight turns. It would stutter the most when backing up. I figured it must be one of the differentials, and my brother agreed. He concluded it could be a torque bind. We still have to flush the coolant, put new engine oil, and put gear oil. BTW, does having almost no gear oil affect this problem?